<!DOCTYPE html>
<html lang="zh_CN">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        *{
            margin: 0;
            padding: 0;
        }

        .container{

            border: 1px solid red;

        }

        .son1{
            width: 200px;
            height: 400px;
            background-color: gold;
            float: left;
        }
        .son2{
            width: 200px;
            height: 300px;
            background-color: green;
            float: right;
        }

        .bottom{

            height: 150px;
            background-color: #4cae4c;

        }

        .clearfix:after{
            content: '';
            display: block;
            clear: both;
        }

        .cls{
            /*clear: both;*/
        }

        .cls:after{
            content: '';
            display: block;
            clear: both;

        }
        
    </style>
</head>
<body>


    <div class="container cls">

        <div class="son1"></div>
        <div class="son2"></div>

        <!--<div class="cls"></div>-->



    </div>


    <div class="bottom"></div>


</body>
</html>